1. Field of the Invention
The present invention relates to cellular telephone systems, and, in particular, to the use of a wireless local loop network with a cellular telephone system.
2. Description of the Related Art
Bluetooth is a wireless telecommunications technology that defines a so-called “wireless local loop” (WLL) or wireless personal area networks (PAN). Bluetooth is being developed by the Bluetooth Special Interest Group, (www.bluetooth.com), which was founded in 1998 by Ericsson, IBM, Intel, Nokia and Toshiba. Bluetooth is an open standard for short-range wireless transmission of digital voice and data between mobile devices, such as laptops, personal digital assistants (PDAs), phones, etc., and desktop devices. At present, there are more than 900 companies that are members of the Bluetooth Special Interest Group, and the general belief is that, in the near future, most telecommunications devices will have Bluetooth technology embedded within them.
Currently, the Bluetooth standard is gaining momentum in the telecommunications industry, not just for WLL, but for other wireless applications as well. However, at present, there are no clearly defined applications for deploying Bluetooth. Nonetheless, the telecommunications industry believes that Bluetooth will extend Internet Protocol (IP) networks to more users and more applications.
Each Bluetooth-enabled device includes a radio and operates in a globally-available frequency band, thereby ensuring communication compatibility worldwide. The Bluetooth standard supports both point-to-point and point-to-multipoint connections. In addition, the Bluetooth standard defines two power levels: a lower power level that covers the shorter personal area, e.g., within a room, and a higher power level that can cover a medium range, e.g., within a building. Software controls and identity coding built into each Bluetooth-enabled device ensure that only those units preset by their owners can communicate with each other.
Bluetooth has certain advantages over cellular networks. For example, it is easier to deploy Bluetooth networks than cellular networks. In addition, Bluetooth networks are more cost-effective in providing WLL services than cellular networks. From a consumer's point of view, the battery life of a mobile phone used in cellular network is less than a cordless phone used in a Bluetooth network. From a service provider's point of view, the cost of supporting mobile phones within buildings is more costly than operating Bluetooth networks.
Nonetheless, there are certain synergies between cellular networks and Bluetooth networks. For example, if a mobile phone can use both types of networks, substantial cost savings are available to the service provider. Moreover, the consumer benefits from the convenience of using only one phone, yet paying less for WLL service than for cellular service. Consequently, there is a need, however, for a system that integrates Bluetooth technology with cellular telephony, so that voice and data can be relayed effectively among these different networks.